Integrating river health into the supply and demand management framework for river basin ecosystem services

Abstract

Healthy rivers provide many beneficial ecosystem services (ESs) to humans in their basins, necessary to achieve high-quality human well-being. The relationship between the supply and demand of ESs in the basin can reflect the coordination level of the basin's ecology and economy. A clear understanding of the relations between ESs supply and demand is the foundation for sustainable river basin ecosystem management. However, there are differences in the health state of different rivers. Unhealthy rivers may be unable to effectively meet the needs of ecosystem services in their basins, thus threatening the ecological health state and sustainable economic development in the basin. Therefore, in this study, a quantitative analysis framework for the supply and demand of river basin ecosystem services (RBES) based on river health states was developed to achieve the basin's rational utilization and sustainable development. Guangdong Province of China was selected, the supply and demand of four ESs relevant to multi-stakeholders (water retention, soil retention, carbon storage, and water purification) in four representative sub-basins were quantified. The ecological supply-demand ratio (ESDR) was introduced to reflect the surplus or shortage of ESs at different river health states. The results showed that the study area exhibited a spatial mismatch between ESs supply and demand. The ESDR of water retention, soil retention, and water purification services in healthy sub-basins were higher than sub-healthy ones, indicating a certain synergy between the health state of the river and its supply and demand state of ES. Implementing targeted spatial management and control is an important measure to ensure the sustainable development of river basins. This study can provide references for sustainable management of river basins and targeted governance under different river health states within and beyond China.